Nistune Forums

I am using a R32 RB26DETT board and I would like the knock warning to work properly, if at all.

Other than that great software.

I have one of those ECUs here. I'll have a look this week at the knock feedback feature of the ECUs again...

That would be great, here in the UK we want to promote the use of the Nissan ECU over the Apexi unit. If you can get the knock feature working properly then that would be the last bit working!!

We recently had a RB20 running a Nistune ecu with standard injectors and 5 bar fuel pressure running 380 BHP at 1.1 bar on a steel turbo.

And who says you need an aftermarket ecu to run over 350 on an RB20???

Martin.

sorry to hijack the thread but just a suggestion/question is it possible to map the engine noise/knock per rpm and load point to accurately point to where the engine is knocking?

I'm looking into it at the moment...

I would like the firmware to continously monitor, and on each comms cycle indicate how many knocks. This can then be fed against maptrace cells as a counter

fantastic

Just trying to find the time to squeze this in. Should get more time tonight

We havent advertised knock functionality with NIStune yet since officially it isnt supported until 100% tested and working. Firmware update on boards will most likely be required once I have it figured out

Dose it work on the SR20 ecu's too? or just the RB motors with the knock board?

At the moment i run an independent knock system. If it were integrated to some degree with all usage (nisboard/normboard+emus) that would be great. I heard knocklite's system was being tested as an input to nistune?

Just to let you guys know where I am at with this...

Current NIStune knock reporting which I was working on last year was done using a knock register from the ECU. It was added to firmware for Z32/R31/CA18/R31 ECUs

All the software support was added to use this, but during testing we found the sample rate was too slow to be effective. The knock flag might be active for only a microsecond, and the ECU code would not capture this as the sampling rate is a lot slower

On one of the Nissan tuning forums, the knock count register for Z32 was 'found' and I have been looking into it. It is a count, but the counts must be consequtive knocks for an increase, and when a scan through the code is performed and there is no knock, then the count decreases

Still not good enough for reporting via the consult interface, since knock may be done by the time consult samples it

What needs to be done in regards to this is that I will have to modify the ECU code to count the number of knock pulses, and then report this via the interface, and then reset the counter. This will give a knock count between samples.

Thats the idea at this stage and I have started with S13 CA18 for prototyping.

I have also hooked up a logic analyser so I can follow the exact path that the code runs through in the ECU, so see what it does with the knock register

I have found so far for R32 that it will immediately use the knock maps and use a detonation timing knock map to determine increments to pull the timing back by. Investigation continues in that area

I also have grabbed PLs knocklite unit and am going to monitor the comms on that to see what I can get from that unit. Need a few nights to investigate that one

If you have another means of getting knock indication, then feed this into one of the wideband inputs in NIStune and select that for knock detection in the interim

Matt,
are you also planning to implement this feature for the s14?

Avner.

I plan to implement it for all ECUs

Since the earlier ECUs have an external knock sensor board, I dont have to play around with trying to get the right frequency into that board. I just inject a pulse train (simulated knock) out from the post filtering on the board to trigger the ECU knock register (it is just an on/off flag which gets monitored by part of the ECU code which effectively checks it some number of microseconds)

The code for S13 CA18/R32/Z32 is effectively the same. They have a knock counter, detonation timing retard table, knock maps

Once I get that going then will work on Z31/R31 which I can test in my vehicle. Those ECUs just pull the timing back say 5 degrees when it gets knock

After that I will do S13/S14/S14A/S15 SR20 which PL will have to test out for me on the dyno since I cant seem to trigger the knock register flag on those ones yet. Not too sure on the exact knock functionality, but assume it would be similar to S13/R32/Z32

Hi Matt

Is there any update when this might become available for the CA18?

Sorry not at this stage yet. I've been going through the main application code and doing bug hunting for problems people have had with some crash issues

You will see from the main downloads page a bug list which I've updated tonight after going through address files people have requested. Once the high / medium priority ones are sorted, and I've sorted out a few side issues which I've received over the weekend then I can continue investigation with the knock warning code

Realistically its going to be a few months before something is tested and available at this stage

Any update about the ECU code modification for Z32 to report knock ?